The search for a concrete that remains clean despite pollution and other environmental discolorations began in the early 1990s as plans were made for building the Dives in Misericordia Church in Rome. Architect Richard Meier wanted a building material for the structure’s three sails that would stay bright. Italcementi Group developed a cement that included a binder containing photocatalysts. Now, the Italian-based cement producer is exporting the technology to its Essroc North American division as TX Millennium cement.